Adsorption of eosin Y dye on Iraqi clay

Abstract

The adsorption characteristics of eosin Y dye dissolved in water on Iraqi clay has been measured in terms of the amount adsorbed, the heat of adsorption and PH of solution.The adsoption isotherm of eosin was found to conform to the Feundlich and Dubinin – Radushkevich equations.The adsoption process was exothermic and physisorption in nature with an enthalpy change ∆H of (-11.87)kJ/mol and ∆G (0.8-2.05) kJ/mol at initial con. = 13.2 ppm.∆S values showed that the process is accompanied by increase in disorder and randomness at the solid- solution interface due to the reorientation of water molecules and eosin around the adsorbent surface.The optimum PH value for eosin Y removal was found to be 3,7,11. The dye was adsorbed on Iraqi clay decrease with increasing the PH of the solution . The eosin Y dye was removed by (25% - 42%) along the whole range of initial concentration at PH equal 3.